Dell Inspiron n5040 HDD failure

This morning, while watching a movie on my laptop, my screen went black and I had a media failure message. I entered DOS to do a diagnostic test, and everything passed except the hard drive, reading it as 0MB and n/a as an icon.

Of course, my system is less than 90 days out of warrenty, so I understand I need to replace the HDD. My question is this, if I purchase a replacement hard drive directly from Dell, will the OS already be installed or will I need to order a replacement boot disk as well?

You'll need a Windows disc as well -- the new drive will arrive blank. If you followed the instructions when you received the system and prepared the recovery media, you can use that. If not, and you're in the US, see

You'll need a Windows disc as well -- the new drive will arrive blank. If you followed the instructions when you received the system and prepared the recovery media, you can use that. If not, and you're in the US, see

That's not what I was referring to. When you first turn on the system, you are prompted to prepare either a flash drive or a set of recovery DVDs -- if you did that, you're all set. If not, you'll need to order a Windows disc.